Human chromosome 3 consists of approximately 200 million base pairs of DNA. Many specific rearrangements affect this chromosome in disorders such as lung and kidney cancer, leukemia, craniofacial and other developmental anomalies, making this chromosome a rich area of biologic interest. Many tools to begin an in depth analysis of this chromosome have been developed. These include: (1) an extensive somatic cell hybrid clone panel which permits the accurate and rapid regional mapping of molecular probes; (2) multiple lambda and cosmid genomic libraries of both the intact chromosome as well as regions thereof; (3) isolation of approximately 170 unique sequence probes from these libraries, including 36 "cluster cosmids" which contain multiple rare restriction endonuclease cleavage sites and which cross-hybridize with high frequency to the DNA of multiple species, and (4) improvements in pulsed-field electrophoretic technology which facilitate the analysis and expand the limits of resolution to approximately 10 million base pairs. With this in mind we propose: (1) To isolate and regionally assign a minimum of 200 unique sequence probes from chromosome 3. If randomly distributed this would provide a molecular probe for every 1000 Kb of DNA. (2) To construct a physical map of the chromosome using these probes and pulsed-field electrophoresis. (3) To identify common restriction fragment length polymorphisms (RFLP's) using these probes. The genetic linkage analysis will be done in collaboration with other investigators.